IR STUDIES OF COORDINATIVELY UNSATURATED SURFACE-COMPOUNDS ON SILICA-GEL .1. CO COMPLEXES OF MANGANESE(II), IRON(II), AND COBALT(II)

Using two different methods of preparation (vacuum heat treatment at 900°C with a pressure below 5 · 10−3 and higher than 10−2 Torr) of the title surface compounds made it possible to investigate several of their CO complexes. The IR bands of the complexes with two CO molecules are interpreted on the basis of the proven assignments of IR spectra of carbonyls as tetrahedral (manganese(II)), cis square‐planar (cobalt(II)) and trans square‐planar (iron(II), cobalt(II)). The known IR spectra of similar chromium(II) CO surface compounds are explained in the same way on the basis of cis and trans square‐planar complexes. Copyright © 1979 Verlag GmbH & Co. KGaA, Weinheim